even 通常指平面上的各点或一条直线的各点处在同一平面或直线上。
flat 指光滑平整的表面，但不一定是水平的。
level 强调没有高低之处，且在同一水平面，可引申指才能相等或与相邻某物平行。
smooth 侧重指表面十分平滑，无任何粗糙的感觉。引申作圆滑解。
参考例句
1. The builders level(l)ed the site and erected a new plant building on it. 建筑者们将场地平整好，然后建造了一个新厂房。
2. Dealing with water level changing ------- wet land. 处理好水位标高的变化-------湿地。
3. However, the ultimate need for very high skill level, need to practice very hard. 不过，这种终极技巧需要非常高的水平，需要非常苦的练习。
英英解释
n.
1. a position on a scale of intensity or amount or quality
2. a relative position or degree of value in a graded group
3. a specific identifiable position in a continuum or series or especially in a process
4. height above ground
5. indicator that establishes the horizontal when a bubble is centered in a tube of liquid
6. a flat surface at right angles to a plumb line
7. a structure consisting of a room or set of rooms at a single position along a vertical scale
8. an abstract place usually conceived as having depth v.
1. aim at
2. tear down so as to make flat with the ground
3. make level or straight
4. direct into a position for use
5. talk frankly with; lay it on the line
6. become level or even adj.
1. having a surface without slope, tilt in which no part is higher or lower than another
2. not showing abrupt variations
3. being on a precise horizontal plane
4. oriented at right angles to the plumb
5. of the score in a contest
